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Arterial hypertension remains the most frequent cardiovascular (CV) risk factor, and is responsible for a huge global burden of disease. Echocardiography is the first-line imaging method for the evaluation of cardiac damage in hypertensive patients and novel techniques, such as 2D and D speckle tracking and myocardial work, provide insight in subclinical left ventricular (LV) impairment that would not be possible to detect with conventional echocardiography. The structural, functional, and mechanical cardiac remodelling that are detected with imaging are intermediate stages in the genesis of CV events, and initiation or intensification of antihypertensive therapy in response to these findings may prevent or delay progressive remodelling and CV events. However, LV remodelling—especially LV hypertrophy—is not specific to hypertensive heart disease (HHD) and there are circumstances when other causes of hypertrophy such as athlete heart, aortic stenosis, or different cardiomyopathies need exclusion. Tissue characterization obtained by LV strain, cardiac magnetic resonance, or computed tomography might significantly help in the distinction of different LV phenotypes, as well as being sensitive to subclinical disease. Selective use of multimodality imaging may therefore improve the detection of HHD and guide treatment to avoid disease progression. The current review summarizes the advanced imaging tests that provide morphological and functional data about the hypertensive cardiac injury.

Cardiac fibrosis represents a serious clinical problem. Development of novel treatment strategies is currently restricted by the lack of the relevant experimental models in a human genetic context. In this study, we fabricated self-aggregating, scaffold-free, 3D cardiac microtissues using human inducible pluripotent stem cell (iPSC)-derived cardiomyocytes and human cardiac fibroblasts. Fibrotic condition was obtained by treatment of cardiac microtissues with profibrotic cytokine transforming growth factor &beta, 1 (TGF-&beta, 1), preactivation of foetal cardiac fibroblasts with TGF-&beta, 1, or by the use of cardiac fibroblasts obtained from heart failure patients. In our model, TGF-&beta, 1 effectively induced profibrotic changes in cardiac fibroblasts and in cardiac microtissues. Fibrotic phenotype of cardiac microtissues was inhibited by treatment with TGF-&beta, receptor type 1 inhibitor SD208 in a dose-dependent manner. We observed that fibrotic cardiac microtissues substantially increased the spontaneous beating rate by shortening the relaxation phase and showed a lower contraction amplitude. Instead, no changes in action potential profile were detected. Furthermore, we demonstrated that contraction of human cardiac microtissues could be modulated by direct electrical stimulation or treatment with the &beta, adrenergic receptor agonist isoproterenol. However, in the absence of exogenous agonists, the &beta, adrenoreceptor blocker nadolol decreased beating rate of fibrotic cardiac microtissues by prolonging relaxation time. Thus, our data suggest that in fibrosis, activated cardiac fibroblasts could promote cardiac contraction rate by a direct stimulation of &beta, adrenoreceptor signalling. In conclusion, a model of fibrotic cardiac microtissues can be used as a high-throughput model for drug testing and to study cellular and molecular mechanisms of cardiac fibrosis.

Background Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic necrotizing vasculitis characterized by hypereosinophilia. EGPA typically develops in three clinical phases, beginning with asthma, followed by tissue eosinophilia and finally systemic vasculitis. Cardiac involvement is the most important predictor of mortality; it occurs in approximately 15–60% of EGPA patients, a significant proportion of whom are asymptomatic and have normal electrocardiogram (ECG) and echocardiogram. Early detection and management of cardiac disease could positevely affect prognosis. Cardiovascular magnetic resonance (CMR) has emerged as the gold standard cardiac imaging technique in the evaluation of cardiomyopathies, due to its ability to reliably assess anatomy, function, and tissue characterization. Aim Purpose of this study was to assess the role of CMR in detecting cardiac disease in patients with EGPA in clinical remission. Methods A dedicated CMR protocol including functional analysis, and pre and post-contrast tissue characterization was performed in 11 patients with EGPA and the results were compared with 11 healthy subjects. Results EGPA patients had lower left ventricular ejection fraction compared to controls (56 ± 19 vs 68.7 ± 5.2, p value 0.02). Late gadolinium enhancement (LGE), representing replacement fibrosis, was positive in 9/11 (82%) patients, mainly with a non-ischemic pattern. In 3/11 (27%) patients a left ventricular thrombus was detected; in 3/11 (27%) patients myocardial edema was detected. CMR parameters of interstitial fibrosis were significantly more elevated in EGPA patients compared to controls. Conclusions Patients with EGPA in clinical remission showed a high cardiovascular burden as demonstrated by lower EF, signs of active inflammation, presence of interstitial and replacement fibrosis and intraventricular thrombosis. Further studies on wider populations are warranted to better understand how these findings could impact on prognosis and eventually guide therapy.

Cardiac adverse remodeling is characterized by biological changes that affect the composition and architecture of the extracellular matrix (ECM). The consequently disrupted signaling can interfere with the balance between cardiogenic and pro-fibrotic phenotype of resident cardiac stromal primitive cells (CPCs). The latter are important players in cardiac homeostasis and can be exploited as therapeutic cells in regenerative medicine. Our aim was to compare the effects of human decellularized native ECM from normal (dECM-NH) or failing hearts (dECM-PH) on human CPCs. CPCs were cultured on dECM sections and characterized for gene expression, immunofluorescence, and paracrine profiles. When cultured on dECM-NH, CPCs significantly upregulated cardiac commitment markers (CX43, NKX2.5), cardioprotective cytokines (bFGF, HGF), and the angiogenesis mediator, NO. When seeded on dECM-PH, instead, CPCs upregulated pro-remodeling cytokines (IGF-2, PDGF-AA, TGF-&beta, ) and the oxidative stress molecule H2O2. Interestingly, culture on dECM-PH was associated with impaired paracrine support to angiogenesis, and increased expression of the vascular endothelial growth factor (VEGF)-sequestering decoy isoform of the KDR/VEGFR2 receptor. Our results suggest that resident CPCs exposed to the pathological microenvironment of remodeling ECM partially lose their paracrine angiogenic properties and release more pro-fibrotic cytokines. These observations shed novel insights on the crosstalk between ECM and stromal CPCs, suggesting also a cautious use of non-healthy decellularized myocardium for cardiac tissue engineering approaches.

Danon disease is a severe X-linked disorder caused by deficiency of the lysosome-associated membrane protein-2 (LAMP-2). Clinical manifestations are phenotypically diverse and consist of hypertrophic and dilated cardiomyopathies, skeletal myopathy, retinopathy, and intellectual dysfunction. Here, we investigated the metabolic landscape of Danon disease by applying a multi-omics approach and combined structural and functional readouts provided by Raman and atomic force microscopy. Using these tools, Danon patient-derived cardiac tissue, primary fibroblasts, and human induced pluripotent stem cells differentiated into cardiomyocytes (hiPSC-CMs) were analyzed. Metabolic profiling indicated LAMP-2 deficiency promoted a switch toward glycolysis accompanied by rerouting of tryptophan metabolism. Cardiomyocytes&rsquo, energetic balance and NAD+/NADH ratio appeared to be maintained despite mitochondrial aging. In turn, metabolic adaption was accompanied by a senescence-associated signature. Similarly, Danon fibroblasts appeared more stress prone and less biomechanically compliant. Overall, shaping of both morphology and metabolism contributed to the loss of cardiac biomechanical competence that characterizes the clinical progression of Danon disease.

Heart failure (HF) disease progression is related to numerous adaptive processes including cardiac fibrosis, hypertrophy and apoptosis by activation of the ‘fetal’ gene program and downregulation of mRNA signatures, suggesting the importance of molecular mechanisms that suppress mRNA steady-state levels. miRNAs (miRs) are small, noncoding RNAs that bind mRNAs at their 3′-UTRs, leading to mRNA degradation or inhibition of protein translation. Several miRs are unregulated in response to cellular stress and can modify cellular functions such as proliferation, differentiation and programmed death; these miRs are also regulated in cardiac disease. Cardiac resynchronization therapy improves cardiac performance and myocardial mechanical efficiency. . In this updated critical appraisal we report on the main miRs that play a key role in response to cardiac resynchronization therapy (i.e., responder vs nonresponder HF patients), focusing on the miR-mediated modulation of cardiac angiogenesis, apoptosis, fibrosis and membrane ionic currents.

In cardiac fibrosis, following an injury or a stress, non-functional fibrotic tissue substitutes normal myocardium, thus leading to progressive heart failure. Activated fibroblasts are principal determinants of cardiac fibrosis by producing excessive fibrotic extracellular matrix and causing hypertrophy of cardiomyocytes. Epigenetic changes, such as DNA methylation, histone modifications, and miRNAs have been involved in these mechanisms. Therefore, there is a strong interest in reverting such epigenetic transformations in order to arrest myocardial fibrotic degeneration. Demethylating agents, such as 5-aza-2'-deoxycytidine, 5-azacytidine, some selective histone deacetylase inhibitors, including mocetinostat, trichostatin A, and MPT0E014, have a direct action on important inducers of cardiac fibrosis. Also dietary compounds, such as resveratrol, can suppress the differentiation of fibroblasts to myofibroblasts. Although in vivo and in vitro studies suggest specific epigenetic therapies to treat cardiac fibrosis, the related clinical trials are still lacking. A better understanding of the epigenetic effects of dietary compounds (e.g. curcumin and green tea catechins) on the onset and progression of cardiac fibrosis, will allow the identification of protective dietary patterns and/or the generation of novel potential epidrugs.